001package org.apache.lucene.demo.facet;
002
003/*
004 * Licensed to the Apache Software Foundation (ASF) under one or more
005 * contributor license agreements.  See the NOTICE file distributed with
006 * this work for additional information regarding copyright ownership.
007 * The ASF licenses this file to You under the Apache License, Version 2.0
008 * (the "License"); you may not use this file except in compliance with
009 * the License.  You may obtain a copy of the License at
010 *
011 *     http://www.apache.org/licenses/LICENSE-2.0
012 *
013 * Unless required by applicable law or agreed to in writing, software
014 * distributed under the License is distributed on an "AS IS" BASIS,
015 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
016 * See the License for the specific language governing permissions and
017 * limitations under the License.
018 */
019
020import java.io.IOException;
021import java.util.ArrayList;
022import java.util.List;
023
024import org.apache.lucene.analysis.core.WhitespaceAnalyzer;
025import org.apache.lucene.document.Document;
026import org.apache.lucene.facet.DrillDownQuery;
027import org.apache.lucene.facet.FacetResult;
028import org.apache.lucene.facet.Facets;
029import org.apache.lucene.facet.FacetsCollector;
030import org.apache.lucene.facet.FacetsConfig;
031import org.apache.lucene.facet.sortedset.DefaultSortedSetDocValuesReaderState;
032import org.apache.lucene.facet.sortedset.SortedSetDocValuesFacetCounts;
033import org.apache.lucene.facet.sortedset.SortedSetDocValuesFacetField;
034import org.apache.lucene.facet.sortedset.SortedSetDocValuesReaderState;
035import org.apache.lucene.index.DirectoryReader;
036import org.apache.lucene.index.IndexWriter;
037import org.apache.lucene.index.IndexWriterConfig;
038import org.apache.lucene.index.IndexWriterConfig.OpenMode;
039import org.apache.lucene.search.IndexSearcher;
040import org.apache.lucene.search.MatchAllDocsQuery;
041import org.apache.lucene.store.Directory;
042import org.apache.lucene.store.RAMDirectory;
043
044/** Shows simple usage of faceted indexing and search,
045 *  using {@link SortedSetDocValuesFacetField} and {@link
046 *  SortedSetDocValuesFacetCounts}.  */
047
048public class SimpleSortedSetFacetsExample {
049
050  private final Directory indexDir = new RAMDirectory();
051  private final FacetsConfig config = new FacetsConfig();
052
053  /** Empty constructor */
054  public SimpleSortedSetFacetsExample() {
055  }
056
057  /** Build the example index. */
058  private void index() throws IOException {
059    IndexWriter indexWriter = new IndexWriter(indexDir, new IndexWriterConfig(
060        new WhitespaceAnalyzer()).setOpenMode(OpenMode.CREATE));
061    Document doc = new Document();
062    doc.add(new SortedSetDocValuesFacetField("Author", "Bob"));
063    doc.add(new SortedSetDocValuesFacetField("Publish Year", "2010"));
064    indexWriter.addDocument(config.build(doc));
065
066    doc = new Document();
067    doc.add(new SortedSetDocValuesFacetField("Author", "Lisa"));
068    doc.add(new SortedSetDocValuesFacetField("Publish Year", "2010"));
069    indexWriter.addDocument(config.build(doc));
070
071    doc = new Document();
072    doc.add(new SortedSetDocValuesFacetField("Author", "Lisa"));
073    doc.add(new SortedSetDocValuesFacetField("Publish Year", "2012"));
074    indexWriter.addDocument(config.build(doc));
075
076    doc = new Document();
077    doc.add(new SortedSetDocValuesFacetField("Author", "Susan"));
078    doc.add(new SortedSetDocValuesFacetField("Publish Year", "2012"));
079    indexWriter.addDocument(config.build(doc));
080
081    doc = new Document();
082    doc.add(new SortedSetDocValuesFacetField("Author", "Frank"));
083    doc.add(new SortedSetDocValuesFacetField("Publish Year", "1999"));
084    indexWriter.addDocument(config.build(doc));
085    
086    indexWriter.close();
087  }
088
089  /** User runs a query and counts facets. */
090  private List<FacetResult> search() throws IOException {
091    DirectoryReader indexReader = DirectoryReader.open(indexDir);
092    IndexSearcher searcher = new IndexSearcher(indexReader);
093    SortedSetDocValuesReaderState state = new DefaultSortedSetDocValuesReaderState(indexReader);
094
095    // Aggregatses the facet counts
096    FacetsCollector fc = new FacetsCollector();
097
098    // MatchAllDocsQuery is for "browsing" (counts facets
099    // for all non-deleted docs in the index); normally
100    // you'd use a "normal" query:
101    FacetsCollector.search(searcher, new MatchAllDocsQuery(), 10, fc);
102
103    // Retrieve results
104    Facets facets = new SortedSetDocValuesFacetCounts(state, fc);
105
106    List<FacetResult> results = new ArrayList<>();
107    results.add(facets.getTopChildren(10, "Author"));
108    results.add(facets.getTopChildren(10, "Publish Year"));
109    indexReader.close();
110    
111    return results;
112  }
113  
114  /** User drills down on 'Publish Year/2010'. */
115  private FacetResult drillDown() throws IOException {
116    DirectoryReader indexReader = DirectoryReader.open(indexDir);
117    IndexSearcher searcher = new IndexSearcher(indexReader);
118    SortedSetDocValuesReaderState state = new DefaultSortedSetDocValuesReaderState(indexReader);
119
120    // Now user drills down on Publish Year/2010:
121    DrillDownQuery q = new DrillDownQuery(config);
122    q.add("Publish Year", "2010");
123    FacetsCollector fc = new FacetsCollector();
124    FacetsCollector.search(searcher, q, 10, fc);
125
126    // Retrieve results
127    Facets facets = new SortedSetDocValuesFacetCounts(state, fc);
128    FacetResult result = facets.getTopChildren(10, "Author");
129    indexReader.close();
130    
131    return result;
132  }
133
134  /** Runs the search example. */
135  public List<FacetResult> runSearch() throws IOException {
136    index();
137    return search();
138  }
139  
140  /** Runs the drill-down example. */
141  public FacetResult runDrillDown() throws IOException {
142    index();
143    return drillDown();
144  }
145
146  /** Runs the search and drill-down examples and prints the results. */
147  public static void main(String[] args) throws Exception {
148    System.out.println("Facet counting example:");
149    System.out.println("-----------------------");
150    SimpleSortedSetFacetsExample example = new SimpleSortedSetFacetsExample();
151    List<FacetResult> results = example.runSearch();
152    System.out.println("Author: " + results.get(0));
153    System.out.println("Publish Year: " + results.get(0));
154
155    System.out.println("\n");
156    System.out.println("Facet drill-down example (Publish Year/2010):");
157    System.out.println("---------------------------------------------");
158    System.out.println("Author: " + example.runDrillDown());
159  }
160}